Mobile phones, personal digital assistants, notebook computers, digital cameras and digital camcorders have become some of the most ubiquitous consumer electronics in recent years. Handheld devices, such as mobile phones, with positioning system have become increasingly prevalent and, as a result, the geographic location of a given handheld device may now be determined according to the wireless positioning signals sent from a positioning satellite. Providing value-added applications to handheld devices has become a focus of research and design for manufacturers.